pci-6289 delay

[chiplearner]

Hi guys

I am facing a problem with simultaneous clocking and triggering capabilities of the PCI-6289 Multifunction Daq card. To facilitate easier understanding the application i am working on is bench characterization of adc using the PCI-6289 , I use the 16 bit D/A onboard the card to generate the input signal to the adc , each time a conversion happens the adc puts out a pulse signal , I use the pulse signal as an clock for the data acquistion to happen exactly each time an conversion is done.

The thing is I want the signal generation and data acquistion to be synchronized perfectly , have tried a couple of variations of programs in Labview .I have attached two versions of the programs , one uses the more basic data acquistion functions to generate the signal and try to acquire it at the same time after averaging out some samples , the other version tries to use the daq assistant to try and synchronize the data acquistion with the generation .

In each version there appears a small delay which translates to code offset in the very begginning , The daq assistant grays out the triggering area which i suppose could be used for making sure the data acquistion only happens when the signal is present and only when the conversion pulse is high.

If anybody could suggest a way for the clocking and triggering using either daq assitant or the more basic vi's ,it would be great.

Also if it could be clarified if this is a limitation of the card would appreciate it.

thank you

Chiplearner

[devchander]

What you need to do is perform Multi function Synchronization

Read this link to understand Multi function synchronization

Also search in Examples shipped with LabVIEW to find Multi function synchronization example VI's

Find examples>>Hardware input output>>DAQmx>>Synchronization>>Multi function folder

Message Edited by devchander on 08-23-2006 03:27 AM

[Neil_S.]

Chiplearner,

The examples suggested by devchandler are execellent resources to get started.  I would add that for your application a shared sample clock may be more suitable than a shared start trigger.  Let me know if you have questions about any of the examples in either the LabVIEW Example finder (Help >> Find Examples) or with the M-Sereis Synchronization document.  Good luck with your application.

Regards,

Neil S.
Applications Engineer
National Instruments